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TY - THES AU - Stratmann, Ina TI - Genauigkeit und Grenzen von Kohlepapier und Druckmessfolie im Kontakt Hertz’scher Körper und von Rad und Schiene; 1. Auflage VL - 6 PB - RWTH Aachen University VL - Dissertation CY - Aachen M1 - RWTH-2025-05813 SN - 978-3-98555-292-4 T2 - Schriftenreihe Schienenfahrzeuge und Transportsysteme SP - 1 Online-Ressource : Illustrationen PY - 2025 N1 - Druckausgabe: 2025. - Auch veröffentlicht auf dem Publikationsserver der RWTH Aachen University N1 - Dissertation, RWTH Aachen University, 2025 AB - As part of the expansion of the local public transport, the aim is to increase the frequency of rail services, which means that the rails and particularly the wheels of rail vehicles will be exposed to higher stresses than is currently the case. From a mate-rials engineering point of view, this represents a challenge, as the contact surfaces between wheel and rail are considerably smaller than in road vehicles. However, with loads of more than 1,000 MPa, the loads acting on them are significantly higher than in road traffic. The shape, size, and position of the contact surface influence the rolling friction and thus the wear. Simultaneously, the contact surface influences the polygonization of the wheels. These relationships lead to considerable research interest in determining the contact area in terms of its size and shape for a more comprehensive understanding of the wheel-rail contact with regard to wear in modern rail vehicles. The evaluation of the contact area can be done via analytical, experimental, or numerical methods. In this research, the contact area is determined using the numerical finite element analysis (FEA) with subsequent knowledge-based experimental validation of the numerical results. Pressure measurement films and carbon paper combined with conventional paper are suitable for the experimental determination of the contact surfaces. The corresponding intermediate layers lead to a changed contact situation, which has to be implemented simulatively. The simulative consideration of these intermediate layers and the required material models are the starting point of this work. Initially, material models were developed for three single-layer pressure measurement films and for carbon paper in combination with conventional paper. The basis for determining the material models of the pressure measurement films was results of experimental investigations of a spherical body with a flat plate. Based on the results of these investigations, elasto-plastic material models were developed, which were afterwards not transferable to the wheel-rail contact. Subsequently, linear-elastic material models were developed for three types of pressure measurement film. A simplified material model was mathematically derived for carbon paper in combination with conventional paper, as no experimental results were available from prior investigations with spherical bodies and plates. The linear-elastic material models for carbon paper and pressure measurement films were extended by pressure-overclosure curves, which took the surface roughness of the wheel-rail contact into account. To validate the material models, a test rig was developed at the beginning of this research, which was used to experimentally generate impressions of the wheel-rail contact. The experimental and simulative investigations comprehensively demonstrated that pressure measurement films and carbon paper are suitable as a valid measuring medium and can be validly mapped via simulations. Carbon paper combined with conventional paper can be used in the same way as pressure measurement films to detect the wheel-rail contact situation. LB - PUB:(DE-HGF)11 ; PUB:(DE-HGF)3 DO - DOI:10.18154/RWTH-2025-05813 UR - https://publications.rwth-aachen.de/record/1013945 ER -